The overall objective of this research is to delineate the influence of the level and composition of dietary fat and air pollutants, particularly ozone, on the formation of lipofuscin substances associated with aging in animal tissues using the rat as the animal model. A particular phase of this research will be to define the influence of increasing age on the metabolism of lipids relative to effects of dietary fatty acid composition on the interconversion of unsaturated fatty acids and serum lipoprotein level and composition. The accumulation of fluorescence substances in the tissues will be correlated with the accumulation of aging pigment determined by light and electron microscopy. It is proposed to develop a method for the quantitative analysis of lipofuscin substances in animal tissues by high performance liquid chromatography in conjunction with a fluorescence detector.